Random Questions

Hi,

Thanks a bunch. I don't see a hole there,surely that doesn't just stick on, that seems kind of iffy for a quality vintage Jap.

On my bike, and I suspect yours too, that cushion (#7 in the parts fiche picture above) is installed on the bottom of the frame near the left rear passenger foot peg. Hopefully there is proper clearance with your aftermarket exhaust. Most aftermarket 4-n-1 exhausts are on the right side.


Thank you for your indulgence,

BassCliff

[bwringer]

What is it on the petcock that is going bad if it isn't a bad o-ring for diaphram. The rest is cast. Also, is there really enough pressure from the tank to break the seal at the float valve? Many motorcycles merely have an on/off and I have never had a problem leaving one on in the parking lot.

It looks like 2 out of four of my needle valves are not sealing properly, probably some cheap Chinese parts.

Many before you have been down the path of petcock denial...

All the rubber bits inside the petcock can go bad and evidently are bad on your bike. Plus, the cast metal body of the petcock very often corrodes and becomes unusable. The rebuild kits are expensive, shoddy junk, so replacement is the safest option.

I prefer not to take chances with a valve that controls the flow of a highly flammable substance a few inches from the ol' twig-n-berries...



Even if they're in perfect condition (in your case, they may or may not be fine but they are likely dirty with corrosion from the bad petcock and thus not able to close), the float needle valves on a GS are not designed to keep gas in the tank indefinitely. Hence the automatic vacuum petcock. If you changed to a manual petcock, you'd still need to shut it off every time you walked away from the bike.

YMMV, but there have been many reports of GS riders who left their petcocks on "Prime" and returned the following morning to a crankcase full of gas.

Yes, there are some other brands of bikes that use rubber-tipped float needles that seal a bit better in the parking lot, and thus it may be relatively safe to leave a manual petcock on for the day. But on a GS, even a perfectly functioning float and needle valve can and will seep.

It looks like 2 out of four of my needle valves are not sealing properly, probably some cheap Chinese parts.

What is it on the petcock that is going bad if it isn't a bad o-ring for diaphram. The rest is cast. Also, is there really enough pressure from the tank to break the seal at the float valve? Many motorcycles merely have an on/off and I have never had a problem leaving one on in the parking lot.

[bwringer]

Thanks BassCliff, I have not done this on a four cylinder before. The method seems straight forward and precise. I'll get it right just as soon as I fix the #2 carb which decided to prop open all night losing about a gallon of gas and hydro-locking the cylinder. Time to pull the dang carbs, again, break it down and see what's up, as well as change my brand new $30's worth of oil that is now likely contaminated.

And see why the petcock isn't closing.....

Both issues have the same cause - mung in the petcock. It's getting into the carbs and propping the float needles open.

As with every revived GS, you need a new petcock.

And no, the rebuild kits usually don't work.

And see why the petcock isn't closing.....

Thanks BassCliff, I have not done this on a four cylinder before. The method seems straight forward and precise. I'll get it right just as soon as I fix the #2 carb which decided to prop open all night losing about a gallon of gas and hydro-locking the cylinder. Time to pull the dang carbs, again, break it down and see what's up, as well as change my brand new $30's worth of oil that is now likely contaminated.

[Steve]

There is usually a rubber stop that hits a pad on the pipe. Or maybe your pipe is bent up a bit. I don't remember seeing any grease fittings on the swingarm pivots, so disassembly might be required. I'm not sure about yours but most of the forks that require air don't take too much. 8-10psi? someone will tell me I'm full of crap I'm sure.

OK, "you're full of crap", but your information is quite accurate.

.

Hi,

There is not really a "factory setting" as these screws were set very lean at the factory and then capped so that us mere mortals couldn't mess with them and violate EPA mandates. Your setting is close but all screws might not have to be set the same.

These are "idle mixture screws", "pilot screws" in the manual, and NOT 'air screws' or 'fuel screws'. Use the "Highest Idle Method" to set them. See:

Plug Chop and
Idle Mixture Adjust Methods
(by Mr. koolaid_kid,Mr. tkent02, Mr. psyguy)

Another way of setting them is to start with the screws too far out, too much idle mixture, and slowly turn them in until you hear the engine speed just start to decrease. Then turn it back out 1/8th turn. Do one cylinder at a time.

Thank you for your indulgence,

BassCliff

Thanks guys, I think I've got the cushion figured out, I put 4psi in the forks and they feel about right, maybe a little stiff. The swingarm I think I'll put off a month or so. Now I took it for it's first ride in about twenty years yesterday. Runs great, accellerates nicely, just the slightest noticeable lack of power until about 3500rpm, and pops a fair bit while engine braking. This is a 1982 GS850gl, I set the pilot screw 2.25 turns out, anyone know the factory setting? I looked through the pilot setting thread but couldn't find this model, I saw the '80 but I think it's different.

[bwringer]

Thanks a bunch. I don't see a hole there,surely that doesn't just stick on, that seems kind of iffy for a quality vintage Jap.

The hole for the rubber cushion would be part of the stock exhaust -- the cushion mounts to the exhaust, not the stand.

You mentioned it has an aftermarket exhaust, so no hole. Some aftermarket exhausts required removing the centerstand.

You'll need to improvise something else, perhaps by attaching a rubber bushing to the centerstand, assuming this is the part of the centerstand that hits the exhaust first.

[bwringer]

You might be able to work some grease into them while assembled, but I believe you'd need to remove the swingarm to grease the bearings properly. Not as horrible a project as it sounds, actually.

Make SURE you find the appropriate section in the manual and follow these instructions carefully to set the bearing preload and position the swingarm correctly.

Thanks a bunch. I don't see a hole there,surely that doesn't just stick on, that seems kind of iffy for a quality vintage Jap.

Hi,

Thanks for the bushing tip, no problem with that melting?

I've never noticed them melting and making a sticky, gooey mess or anything. They will eventually wear out but they're cheap. I just replace them once in a while, ever couple of years or so.

What you really need for the center stand is #7 in the parts fiche picture below:



Part# 09321-10001. I think they are still available for a couple of bucks. If your new mufflers get in the way then you may have to come up with another solution.

Thank you for your indulgence,

BassCliff

Thanks for the bushing tip, no problem with that melting?